Humoral Immunity Flashcards
Humoral immunity
Mediated by ________, also called _______, produced by _______ cells.
antibodies (Ab)
immunoglobulin (Ig); Plasma
Antibodies generally are found in _____cellular fluids
Eg ____,____,_______
extra
Blood, lymph, mucus
Antibodies are active against agents with an __________ phase, including some viruses, toxins, and bacterial infections
extracellular
Plasma cells are derived from activated ______ that are produced in the _______
B-cells
bone marrow
B cells
B cells display a single homogenous clonal immunoglobulin molecule on their surface.
These immunoglobulins serve as receptors (B-cell receptors [BCRs]) for a specific antigen
Each B cell can respond to only one antigen or a closely related group of antigens.
All immature B cells carry IgM immunoglobulins on their surface
B cells also have surface receptors for the Fc portion of immunoglobulins and for several complement components.
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B cells
B cells display a single homogenous clonal immunoglobulin molecule on their surface.
These immunoglobulins serve as receptors (B-cell receptors [BCRs]) for a specific antigen
Each B cell can respond to only one antigen or a closely related group of antigens.
All immature B cells carry IgM immunoglobulins on their surface
B cells also have surface receptors for the Fc portion of immunoglobulins and for several complement components.
B cells
B cells display a single _____genous clonal immunoglobulin molecule on their surface.
These immunoglobulins serve as receptors (——————-) for a specific antigen
Each B cell can respond to only ______ antigen or a ___________ of antigens.
homo
B-cell receptors [BCRs]
one ; closely related group
All immature B cells carry Ig____ immunoglobulins on their surface
B cells also have surface receptors for the _______ of immunoglobulins and for several complement components.
M
Fc portion
An antigen interacts with the B lymphocyte that shows the best “______” by virtue of its immunoglobulin surface receptor.
The antigen binds to this BCR, and the B cell is stimulated to _________ and_______
The BCR with its bound antigen is _______ by the B cell and the antigen is ______________ that are then ___________________
fit
divide and form a clone (clonal selection).
internalized; degraded to yield peptides
returned to the cell surface bound to MHC class II molecules.
B cell receptor
MHC class ___– peptide complex on B cells is recognized by antigen-specific ________ cells.
CD____ ligand on T cells binds to CD___ on B cells, and the T cell produces cytokines, such as, _____,______,_____ which induce B-cell proliferation.
II; helper (CD4) T
40; 40
IL-4, IL-5, and IL-6,
Bcell receptor
Activated B cells migrate into ______ and proliferate to form __________ that now differentiate into either ________________ cells or ________ cells.
follicles
germinal centers
antibody-producing plasma
Structure of an Antibody Structure of an Antibody
Antibody composed of ______ chains and _______ chains.
These chains bind together to make a ____ shaped molecule
two heavy
two light
Y
The structure of Antibodies may be described by the way they are ___________ by _______.
The stem portion is referred to as the _________
The Y portion with the top third of the stem is referred to as the _____ region.
cut and digested; proteases
Fc region
Fab
Antibodies
The FC region often acts as the _____ for phagocytes during _______ or ______________ cytotoxicity.
The Fab region contains the ————- region
receptor
opsonisation
Antibody dependent cell mediated
antigen binding
The structure of Antibodies
The two sections located at the ends of Y’s arms are called ________ regions.
The variable region is structurally _______ for all ______________________
variable (V)
identical
antibodies synthesized by a particular plasma cell.
The Antibodies from each plasma cell however are different or unique from all other antibodies produced by other plasma cell.
T/F
T
Structure of antibodies
The stem of the antibody molecule as well as the lower portion of the arms called ————— regions.
Most H chains consist of _______ domain (VH) and _________ constant domains (CH).
constant (c)
one variable
three or more
Structure of antibodies
Variable regions are responsible for _____________
constant regions are responsible for the __________ described below:
All plasma cells in the body are _______________
A particular plasma cell may _______________________ producing in order to fight an infection in a different way.
antigen binding
biologic functions
producing one of these classes of antibodies.
switch the particular class of Antibody that it is
Ig___ is the first and main immunoglobulin produced early in the primary immune response.
M
IgM
IgM is present on the surface of virtually _____________ B cells.
It is composed of __________ units (each similar to one Ig____ unit) and ____ molecule of _____ chain
_______mer
____ units held together by _____ bonds
all uncommitted
five H2L2 ; G
one; J (joining)
Penta
5; disulfide